Yarı katı şekillendirilmiş AlSi12 alüminyum alaşımında Ag ilavesinin mikroyapıya etkisinin incelenmesi

Abstract

Bu çalışmanın temel amacı yarı katı halde şekillendirilmiş AlSi12 alaşımına eser miktarda Ag elementi ilavesinin malzemenin mikroyapısına ve mekanik özelliklerine etkilerini ortaya koymaktır.  Yarı katı halde şekillendirmenin intermetalik morfolojisi, Si oluşumu ve küresel α-Al morfolojileri üzerinde önemli bir etkiye sahip olduğu sonucuna varılmıştır. İntermetalikler yarı katı halde şekillendirme esnasında kırılmaktadır. Ayrık Si partikülleri hem yarı katı hem de tikso şekillendirmede gözlenmiştir ve mekanik özelliklere önemli katkısı olmuştur. 

Keywords

• AlSi alaşımları,intermetalik fazlar,mekanik özellikler,Ag ilavesi,yarı katı şekillendirme

Investigation of microstructure effect of Ag addition in Thixo forming AlSi12 aluminum alloy

Abstract

The main objective of this study is to reveal the effect of the Thixo process on the microstructure and mechanical properties of the AlSi12 alloy with trace amounts of silver. It is concluded that Thixo has an important effect on the morphology of intermetallics and Si formation, as well as globular α-Al morphology. The intermetallics have been fractured during thixo. It is believed that the fine distribution of the intermetallics is one mechanism for the improved mechanical properties of Thixo alloys. The discrete Si particles have been observed during both isothermal heating and Thixo and have an important effect on mechanical properties.

Keywords

• AlSi alloys,intermetallic phases,mechanical properties,Ag addition,thixo forming

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